/Engine/Source/Editor/UMGEditor/Public/WidgetBlueprintCompiler.h
void AddExtension ( [UWidgetBlueprintGeneratedClass](API\Runtime\UMG\Blueprint\UWidgetBlueprintGeneratedClass) * Class, [UWidgetBlueprintGeneratedClassExtension](API\Runtime\UMG\Extensions\UWidgetBlueprintGeneratedClassEx-) * Extension )